public class test2 {
    public static void main(String[] args) {
        /**
         * Definition for singly-linked list.
         * class ListNode {
         *     int val;
         *     ListNode next;
         *     ListNode(int x) {
         *         val = x;
         *         next = null;
         *     }
         * }
         */
        }
    }

